Sir Chris is honorary president of Friends Of Blencathra, set up in 2014 after the Earl of Lonsdale put the peak, known as Saddleback, on the market for £1.75 million.
The group wanted to make sure Blencathra remained for the community and raised more than £250,000 to buy it.
Lord Lonsdale wanted to sell the 2,850ft mountain to help meet a £9 million inheritance tax bill without causing pain and disruption to those working or living on his estate.
He has since paid the bill using other assets and Blencathra was taken off the market. People are now calling on the charity to return donations.
Sir Chris said: “I am getting increasingly concerned about the situation and have urged the chairman David Wheeler to keep all the donors fully in the picture.”
He added that as the group’s president, he was a figurehead and did not attend trustees’ meetings.
Mr Wheeler said the group was still pursuing the acquisition of the mountain so the trustees were not in a position to consider the option of refunding donations.
John Robson, agent for Lord Lonsdale, said: “There’s no direct negotiations going on with Friends Of Blencathra and we’re not interested in talking to them.”
Mr Wheeler said: “The asking price is now considerably higher than the valuations we have received for the property. We will review the situation again at the end of September when we hope to have more clarity and are able to revise our offer.”
The campaign to have the mountain brought into community ownership attracted massive and immediate support when Saddleback was put up for sale.
A huge fundraising campaign got underway, although the final amount pledged has never been made public for commercial reasons. People from all over the region and beyond backed the campaign, including prominent figures including adventurer Ben Fogle as well as Sir Chris.
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